- G.729a
G.729a is an audio data compression algorithm for voice that compresses voice audio in chunks of 10 milliseconds. G.729a is compatible with
G.729 , but requires less computation. This lower complexity is not free since speech quality is marginally worsened.Development
The
codec was developed by a consortium of organisations: France Telecom, Mitsubishi Electric Corporation, Nippon Telegraph and Telephone Corporation (NTT), and Université de Sherbrooke.The intellectual property rights (IPR) for this codec are maintained by SIPRO (http://www.sipro.com/).
Features
* Sampling frequency 8 kHz/16-bit (80 samples for 10 ms frames)
* Fixed bit rate (8 kbit/s 10 ms frames)
* Fixed frame size (10 bytes for 10 ms frame)
* Algorithmic delay is 15 ms per frame, with 5 ms look-ahead delay
* G.729a is a hybrid speech coder which uses Algebraic Code Excited Linear Prediction (ACELP )
* The complexity of the algorithm is rated at 15, using a relative scale whereG.711 is 1 andG.723.1 is 25.
* G.729 Annex B defines 2 byte Silence Insertion Descriptor (SID) frame for Comfort Noise Generation
*PSQM testing under ideal conditions yields Mean Opinion Scores of 4.04 for G.729a, compared to 4.45 forG.711 (u-law)
*PSQM testing under network stress yields Mean Opinion Scores of 3.51 for G.729a, compared to 4.13 forG.711 (u-law)See also
*
G.711 (a-law and mu-law/u-law)
*G.722
*G.722.1
*G.723
*G.723.1
*G.726
*G.728
*G.729
*G.729.1
*List of codecs
*AMR
*AMR-WB
*EFR
*FR
*iLBC
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